Merge branch 'mm/mediawiki-dumb-push-fix'

* mm/mediawiki-dumb-push-fix: git-remote-mediawiki: no need to update private ref in non-dumb push git-remote-mediawiki: use no-private-update capability on dumb push transport-helper: add no-private-update capability git-remote-mediawiki: add test and check Makefile targets